1. Technical Field
The present invention relates to a dynamo apparatus for a boat, wherein the boat has a sail engine and a dynamo apparatus supplying electric power to the inboard.
2. Background Art
A propelling device of a boat comprises an engine and a power transmission device. Driving force of the engine is reduced in speed by the power transmission device and then drives a screw connected to the power transmission device. A dynamo apparatus is disposed between the engine and the power transmission device. The engine output drives the dynamo apparatus while driving the screw, and the output electric power of the dynamo apparatus is supplied to the inboard. Such an art is disclosed by the Patent Literature 1 or 2.
With regard to construction of the above-mentioned conventional dynamo apparatus, it is cooled by making cooling water pass inside the dynamo apparatus. It is thus necessary to provide a pump taking cooling water in and a cooling water circuit. Accordingly, the whole construction including the dynamo apparatus is complicated, the part number is increased and the cost is increased compared to the present invention.
With regard to construction the cooling air passes inside the dynamo apparatus. It is thus necessary only to provide a cooling fan and to form air holes in a casing of the dynamo apparatus. Accordingly, the construction is simpler than that of the construction using cooling water. For example, the Patent Literature 3 discloses the construction that the cooling fan is provided in the casing of the dynamo apparatus and the air holes are formed in the outer peripheral surface of the casing. The Patent Literature 4 discloses the construction that the air holes are formed in the outer peripheral surface of the casing constructed cylindrically and the cooling fan is provided inside the casing though the construction is not exclusively for a boat.
Patent Literature 1: the Japanese Patent Laid Open Gazette 2003-81189
Patent Literature 2: the Japanese Patent Laid Open Gazette 2003-81190
Patent Literature 3: the International Publication No. 05/32935
Patent Literature 4: the Japanese Patent Laid Open Gazette Hei. 7-184351